feat(parser): fix token location and print sql with cursor on parse error

[wangrunji0408]

I hereby agree to the terms of the RisingWave Labs, Inc. Contributor License Agreement.

What's changed and what's your intention?

Currently, the location associated with each token is inferred from token length and is not accurate. This PR fixes this problem by inferring location from lower-level chars.

Additionally, this PR appends SQL context to the parse error message.

$ selet 1;
sql parser error: expected an SQL statement, found: selet at line 1, column 1
LINE 1: selet 1;
             ^

Note that the cursor is still not accurate. It may be offset one token forward because the error token has been consumed.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added test labels as necessary. See details.
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

The error messages of parser have improved. It now prints the SQL context around the error, helping users quickly locate issues.